Apollo 10 command module pilot John Young holding up a drawing of Snoopy during a telecast from the Apollo 10 spacecraft on the 19th May 1969. Apollo 10, which had launched on the 18th May, was the fourth crewed mission of the Apollo program and the second to orbit the Moon. It was a dress rehearsal for the Moon landing with the Lunar Module (call sign Snoopy) separating from the Command and Service Module (call sign Charlie Brown) and descending to 15.6 kilometres above the lunar surface.